Volunteered geographic information

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OpenStreetMapper records a hiking trail

Volunteered Geographic Information ( VGI ; 'Voluntarily Collected Geographic Information') denotes the entirety of spatial information that is voluntarily collected, organized and then made available to the public by laypeople so that others can use and process this data. VGI is always based on the targeted recording and sharing of data, such as B. as part of a bird count or when entering a cycle path on OpenStreetMap . This must be distinguished from so-called non-volunteered geographic information , in which users provide data without their knowledge or as passive actors, as is the case with tracking smartphones. VGI applications largely take place in interactive Web 2.0 and have seen strong growth since the mid-2000s.

History of origin

The term Volunteered Geographic Information goes back to the American geographer Michael Goodchild , who first used it in 2007 in an article. The term has now established itself to describe the phenomenon. VGI was also able to establish itself as an interdisciplinary field of research that includes geography and other social sciences .

VGI are primarily seen as a phenomenon of the 21st century, but there have been projects with a VGI character for several decades. The American Audubon Society's Christmas Bird Count dates back to 1900. Volunteers draw up a list of the birds they have observed at a specified time and in a specific area. In Great Britain, when land use began in the 1930s and 1940s, help was also drawn from school classes who conducted surveys.

For the most part, the recording of geospatial data and the cartographic work itself were reserved for the state or surveying agencies in modern times. This is particularly due to the fact that the creation of maps is a complex process and requires a variety of resources: On the one hand, it requires the expertise of a suitably trained cartographer . On the other hand, obtaining information via remote sensing, as well as the subsequent processing, is very expensive. Therefore, v. a. that maps what remained valid for a long time and found as many interested parties as possible. Geographical information and maps were therefore often kept as general as possible in order to be versatile. This resource-intensive process is increasingly causing government agencies to restrict their cartographic activities. On the other hand, there is the steadily growing need for geodata of all kinds, be it in the form of a road map or information about sights in the area. Against this background and in combination with the improved technical possibilities , the VGI movement developed.

At the state level, a stronger involvement of citizens in the acquisition of geographic data can be observed since the mid-1990s. The "National Spatial Data Infrastructure" introduced in the USA in 1994 is an example of this. Mapping work is transferred from government surveying offices to volunteers who record data using precise guidelines. This project is considered to be the forerunner of today's VGI projects. Still, it would be about a decade before the movement became a mass phenomenon. The decisive factors for this are v. a. the user-friendly technologies that are available to many people today.

Technical requirements

Web 2.0 is the basis for VGI. The Internet user is no longer the passive recipient of information, but can design and distribute content himself. The applications are often uncomplicated to use and are widely used. The uploaded data is referred to as user-generated content (UGC). VGI form a sub-category of this with specialization on information that deals with geographic issues of all kinds. Michael Goodchild describes VGI as a product of Web 2.0 and the diverse possibilities of interaction that it offers.

Furthermore, the process of georeferencing has also been steadily simplified, since GPS is now not only available as a standalone receiving device, but also in many smartphones and cameras. Where previously complex equipment was needed, coordinates can now be recorded easily, quickly and with good accuracy using this technology. Alternatively, they can also be called up from applications in the network such as maps. The increasing availability of broadband internet has also contributed to the spread of VGI.

Potentials

Volunteers are experts in local issues. They have in-depth knowledge of their environment and are well informed about current events on site. In a figurative sense, the human being functions as a sensor that records, interprets and reproduces his environment with his senses. Volunteers can therefore find “invisible” information such as B. Contribute informal place names as VGI. But weather data, information about crime, leisure activities or traffic data are also suitable for recording by volunteers.

VGI are also suitable for all those circumstances that appear very briefly or only for a short period of time. A network of volunteers offers the opportunity to react flexibly to relevant events and to record data quickly. In New Jersey, for example, participants in a VGI project map pools that only occur a few weeks a year. On the basis of the database created in this way, the environmental agency can decide whether the relevant areas should be placed under special protection. Rapid absorption and dissemination of information is also particularly relevant in the event of a disaster and when creating crisis maps .

Depending on the expertise and experience of the volunteer, more specific data can also be recorded. So z. B. For a long time, farmers have relied on the state's soil maps, which were very general and did not contain detailed information about the cultivation areas. With the help of new measurement techniques, it is now possible for farmers to determine parameters such as pH value or soil moisture that are relevant for plant cultivation. With this data, you can create a more precise soil map that is specifically tailored to your needs.

To what extent VGI can also be used at the state level remains to be seen. In some areas, the use of volunteers is a good option, e.g. B. if traffic routes are to be mapped or special topographical facts are to be recorded. It is also conceivable that in the future, thanks to improved technology, volunteers will also be able to contribute reliable data to altitude measurements . They can also help to keep existing data up to date. Other topics such as B. Geodesy or orthophotos , however, still require training and / or special equipment and should therefore continue to be the responsibility of the state. The same applies to cadastral maps .

differentiation

In the research literature, there is now a consensus that VGI only refer to data that has been specifically collected by volunteers with the intention of sharing them. The data is collected in a participatory manner. It is therefore necessary to differentiate from the data that is passively collected and provided by users without them necessarily being aware of this. In addition to non-volunteered geographic information , this type of data acquisition is also referred to as "opportunistic". A further developed category of VGI is the data from social media , for which the term Ambient Geospatial Information stands.

Non-Volunteered Geographic Information

The term Non-Volunteered Geographic Information is used for information that is recorded and collected involuntarily or unconsciously. This can be done through devices that those affected actively use themselves, but also through location-based sensors such as surveillance cameras. In 2010 it became known that the iPhone was collecting data from the owner and storing it unencrypted. Location data as well as the corresponding times are saved. Other operating systems such as Android or Windows should proceed in a similar way.

The term Contributed Geographic Information (CGI) goes in a similar direction . He also emphasizes that data is only contributed passively; in most cases there is no control or access to it. CGI often work through so-called "opt-out" rules. This means that users have to accept the terms of use of a service without restriction in order to be able to use it. The Google Map Maker is therefore only activated if you agree that Google receives the rights to the created maps and z. B. can redistribute. When collecting traffic data for its Google Maps service, Google uses an “opt-in” model: Here, the user of an Android operating system must activate both the GPS function and location access using the Google Maps app. Only then is its data automatically used to record the traffic. A traffic jam report therefore means that Android smartphones are currently not moving on the motorway.

Data from social media

Posts in social media also often contain a geographical reference. It differs from VGI in that there is no specific intention behind sharing spatial data, such as: B. the entry in a database and the subsequent processing. The included “geographic footprint” is a side effect. Since information about one's own environment is communicated in this way, it is called Ambient Geospatial Information (AGI). This type of information can be used to discover, localize and accompany special social events and developments at an early stage. In addition to tweets , videos on YouTube and pictures on Flickr also count as AGI if they are given a location. Geographic information can also be read from apps such as Foursquare . The Wall Street Journal evaluated Foursquare data from New York and San Francisco that were collected over a period of one week. Places with increased activity emerged where a particularly large number of users logged into the app, such as B. in restaurants or train stations.

However, posts from social media do not automatically fall under the AGI category. As soon as someone consciously shares spatial data with the intention that this can also be used later by others, this is referred to as VGI. This is e.g. B. the case with a UK snow map. She works with tweets, which in addition to a hashtag must also contain precise information on the location in the form of the postcode. The term VGI is more appropriate for this information.

In the context of AGI, shared whereabouts information can easily be misused. The Please Rob Me application draws attention to how easy it is to find out if someone is not at home and therefore a potential burglary victim. It also combines freely available AGI from Twitter and Foursquare.

Application examples

Non-commercial and open source projects

VGI form the basis of numerous open source projects. In addition to OpenStreetMap , this category also includes Wikimapia . The latter works as an interactive map on which users can enter information about geographical objects. The aim is to record as many places as possible and thus create a comprehensive directory of places. Another example is the Mundraub platform. It collects the locations of fruit trees that are freely accessible to the general public and that can be harvested.

Commercial providers

On the commercial side, applications from Google are among the most prominent examples that support the processing of VGI. The Map Maker allows you to edit maps yourself and to label places. Google also provides an application that can be used to combine Google's map material with other data to create a new thematic map. VGI can also serve as a data basis here. The resulting cards are called a mashup .

Navigation systems such as TomTom also collect anonymized geographic data of their users if they have given their consent. On the one hand, these are used to update your own maps and to create traffic forecasts. In addition, the data is passed on to the road construction authorities, where they serve as a basis for decision-making.

State projects

The US Department of the Interior operates the Did you feel it? Site. Citizens are encouraged to contribute information about earthquakes in their area. The cooperation of those directly affected is intended to ensure that precise information about the extent of an earthquake is available quickly. The data are scientifically processed and also serve to organize help quickly and efficiently. Originally only available in the US, events from all over the world can now be submitted.

The Geographer project of the British Ordnance Survey aims to collect representative photos and information for every square kilometer in Great Britain and Ireland. As of February 2014, the database consisted of nearly 4 million images, which were provided with a description and uploaded by volunteers.

The user - from consumer to producer

The role of the user has undergone a fundamental change in the context of VGI. In the times of traditional cartography, he was a passive consumer of data and maps, which were mostly published by the state. He was mainly seen as a buyer and source of income. The technical developments described opened up new possibilities for the user. He can now create maps himself and pass on information. This novel mix of consumer and producer is summarized under the term “ prosumer ”.

The volunteers are often lay people who have not received any specialist geographic training. This lack of specialist knowledge is compensated for by the easily manageable technical innovations. Even without in-depth knowledge of cartographic processes, maps can be created quickly and easily with the appropriate software.

The motives of the volunteers to take part in a project are very diverse. They include altruism as well as professional interest or the need to belong to a community (in this case e.g. the OpenStreetMap Community). Particularly relevant for VGI collectors is the so-called “pride of place”, ie pride in a certain place. The shared information can be about a location such. B. serve tourism or economic development, or the main thing is that your own place is simply present on a map.

Critical discussion

Quality and quality control

A central question that arises in connection with VGI is that of the quality or quality control of VGI. The volunteers who collect and share VGI can be considered reliable sources of local information, but they typically do not ingest data according to scientific standards. The quality of the information therefore depends to a large extent on how conscientiously and precisely the individual volunteer records it.

A crucial characteristic of data quality is the source: accurate references usually contribute to the credibility of information. In some cases, however, this information cannot be viewed online, is not available at all, or there are so many users involved in a project that it is not possible to check the individual sources. In addition, several sources are often used for a project without being identified. The situation is similar with metadata , which is not added to the data sets by default. It therefore remains difficult to finally assess the quality and to understand the creation and collection process of data sets.

One way of ensuring a certain level of quality in advance is to train the volunteers for their tasks. The skills thus acquired allow the work to be carried out precisely and gain credibility. This method is used, for example, in the Audubon Society's bird counting. There, participants receive specific guidelines for the exact procedure so that the information recorded can be compared.

The following measures serve to test the quality of data that has already been collected. With data already available on platforms, the “wisdom of the masses” enables errors to be found and corrected (so-called Linus's Law). However, this type of control can only be applied to a limited extent to geographical information, as there are not enough people who can correct any incorrect information, especially for remote places. A certain hierarchy in the user groups, which assigns different rights depending on the rank, is more effective. So you can use moderators to review and correct the contributions. With OpenStreetMap, for example, a distinction is made between normal users and the data working group. The latter has extensive access rights and can therefore intervene in cases of vandalism or copyright issues. A comparison with known facts also allows a statement to be made about the quality of new data. If the latter does not match the information available, an error can be assumed. This is e.g. For example, if a map shows a school in the parking lot of a shopping mall. From the context it becomes clear that one of the two pieces of information may not be correct and that it must be checked and, if necessary, changed.

VGI as a “democratization” of cartography?

In connection with VGI, it is often said that they contribute to a democratization of cartography, that is, a broad mass can participate in the process of creating maps and access geographical information on the Internet. However, there are several points of criticism that suggest that this process is possible in principle and is progressing slowly, but is not yet complete.

The technical requirements are not available to the same extent worldwide. So it lacks v. a. in developing countries with the necessary equipment. The term “ digital divide ” makes the differences in technological progress particularly clear. But even within the industrialized countries, urban and rural areas are not equally well connected to the broadband network. These different starting conditions have an impact on the access to information. On the other hand, it can be assumed that fewer VGI are collected in disadvantaged regions and can be found in the network.

Furthermore, it can be observed that only a minority of users of UGC projects such as OpenStreetMap regularly and on a large scale collect data and share it online. The approximate distribution of user activity occurs while in the 90-9-1 rule of Jakob Nielsen expressed: So 90% of users are contributing not own posts but use the applications as passive consumers. 9% occasionally contribute and only 1% is permanently active. Which content is available online or entered on cards therefore also depends on the latter group. The software used often contributes to this uneven distribution, e.g. B. by giving the most active participants a higher rank and thus more extensive rights than occasional users. The latter are hardly motivated to make more of their own contributions.

Which VGI are accepted also depends largely on the individual volunteer. Most of them are male, educated and have a high income, which enables them to purchase the necessary equipment. As a result, more data is recorded in privileged areas, whereas marginalized groups and generally disadvantaged areas are underrepresented in the data.

Differentiation from other terms

In connection with VGI, there are two more terms that only partially match the definition of VGI.

For example, there is also talk of “ crowdsourcing of geodata”. The term "geography" is deliberately omitted here in the technical term. This is to make it clear that VGI is limited to the pure recording of data. Essential parts of the scientific work - e.g. B. the creation of models or the interpretation of the data sets - are reserved for trained scientists.

Furthermore, a distinction must be made with the term “ neogeography ”. Andrew Turner also describes VGI as gathering information. Neogeography, on the other hand, also includes other activities, including visualizing and sharing location-based data. The focus here is more on the individual and how they deal with geographic information in everyday life.

There is still no common equivalent in German. The terms volunteer geography and user-generated geomass data have already been suggested . Based on VGI as a sub-category of UGC, the analogy to the German translation of UGC into user-generated (media) content would lead to the term user-generated geographical information .

literature

  • Sarah Elwood, Michael Goodchild, Daniel Sui: Researching Volunteered Geographic Information. Spatial Data, Geographic Research, and New Social Practice. In: Annals of the Association of American Geographers 102, No. 3, 2012, ISSN  0004-5608 , pp. 571-590.
  • Andrew Flanagin, Miriam Metzger: The credibility of volunteered geographic information. In: GeoJournal. 72, No. 3-4, 2008, ISSN  0343-2521 , pp. 137-148.
  • Michael Goodchild: Citizens as sensors: the world of volunteered geography. In: GeoJournal. 69, No. 4, 2007, ISSN  0343-2521 , pp. 211-221 ( geog.ucsb.edu PDF, slightly modified version).
  • Christian Heipke: Crowdsourcing geospatial data. In: ISPRS Journal of Photogrammetry and Remote Sensing. 65, No. 6, 2010, ISSN  0924-2716 , pp. 550-557.
  • Daniel Sui, Sarah Elwood, Michael Goodchild, Michael (Eds.): Crowdsourcing Geographic Knowledge. Volunteered Geographic Information (VGI) in Theory and Practice. Springer Verlag, Dordrecht 2013, ISBN 978-94-007-4587-2 .

Individual evidence

  1. ↑ a b David Tulloch: Is VGI participation? From vernal pools to video games. In: GeoJournal. 72, No. 3–4, 2008, p. 161.
  2. ^ A b Michael Goodchild: Citizens as sensors: the world of volunteered geography. In: GeoJournal. 69, No. 4, 2007, p. 212.
  3. ↑ a b Christian Heipke: Crowdsourcing geospatial data. In: ISPRS Journal of Photogrammetry and Remote Sensing. 65, No. 6, 2010, p. 554.
  4. ^ A b c Sarah Elwood, Michael Goodchild, Daniel Sui: Researching Volunteered Geographic Information. Spatial Data, Geographic Research, and New Social Practice. In: Annals of the Association of American Geographers 102, No. 3, 2012, p. 572.
  5. ↑ Michael Goodchild: Commentary: whither VGI? In: GeoJournal. 72, No. 3-4, 2008, p. 239.
  6. ^ A b Michael Goodchild: Citizens as sensors: the world of volunteered geography. In: GeoJournal. 69, No. 4, 2007, p. 217.
  7. ^ Sarah Elwood, Michael Goodchild, Daniel Sui: Researching Volunteered Geographic Information. Spatial Data, Geographic Research, and New Social Practice. In: Annals of the Association of American Geographers. 102, No. 3, 2012, p. 574.
  8. ↑ Michael Goodchild: Citizens as sensors: the world of volunteered geography. In: GeoJournal. 69, No. 4, 2007, p. 215.
  9. ↑ Michael Goodchild: Citizens as sensors: the world of volunteered geography. In: GeoJournal. 69, No. 4, 2007, pp. 215-217.
  10. ↑ Andrew Flanagin, Miriam Metzger: The credibility of volunteered geographic information . In: GeoJournal. 72, No. 3–4, 2008, p. 139.
  11. ↑ Michael Goodchild: Citizens as sensors: the world of volunteered geography. In: GeoJournal. 69, No. 4, 2007, p. 218.
  12. ^ A b Sarah Elwood, Michael Goodchild, Daniel Sui: Researching Volunteered Geographic Information. Spatial Data, Geographic Research, and New Social Practice. In: Annals of the Association of American Geographers. 102, No. 3, 2012, p. 577.
  13. ↑ Jamal Jokar Arsanjani: VGI Platforms and Data Generalization . In: Abstracting geographic information in a data rich world. Methodologies and applications of map generalization . 1st edition. Springer International Publishing, Cham 2014, ISBN 978-3-319-00203-3 , pp. 131-139 .
  14. ↑ Stephane Roche, Eliane Propeck-Zimmermann, Boris Mericskay: GeoWeb and crisis management: issues and perspectives of volunteered geographic information. In: GeoJournal. 78, No. 1, 2013, p. 23.
  15. ↑ Michael Goodchild: Commentary: whither VGI? In: GeoJournal. 72, No. 3-4, 2008, p. 241.
  16. ^ Sarah Elwood, Michael Goodchild, Daniel Sui: Researching Volunteered Geographic Information. Spatial Data, Geographic Research, and New Social Practice. In: Annals of the Association of American Geographers. 102, No. 3, 2012, p. 575.
  17. ^ Francis Harvey: To Volunteer or to Contribute Locational Information? Towards Truth in Labeling for Crowdsourced Geographic Information. In: Daniel Sui, Sarah Elwood, Michael Goodchild, Michael (Eds.): Crowdsourcing Geographic Knowledge. Volunteered Geographic Information (VGI) in Theory and Practice. Springer Verlag, Dordrecht 2013: 31-42.
  18. ↑ a b Monika Sester: Integrating and Generalizing Volunteered Geographic Information . In: Abstracting geographic information in a data rich world: methodologies and applications of map generalization . 1st edition. Springer International Publishing, Cham 2014, ISBN 978-3-319-00203-3 , pp. 119-155 .
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  30. ^ MG Siegler: Please Rob Me Makes Foursquare Super Useful For Burglars. In: techcrunch.com. February 17, 2010, accessed May 14, 2019 .
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  33. ↑ This is what we really do with your data ( Memento of the original from September 21, 2013 in the Internet Archive ) Info: The archive link was inserted automatically and has not yet been checked. Please check the original and archive link according to the instructions and then remove this notice. TomTom. Retrieved February 18, 2014. @1@ 2Template: Webachiv / IABot / www.tomtom.com
  34. ^ Numbers Geographer. Retrieved February 18, 2014.
  35. ↑ David Coleman, Yola Georgiadou, Jeff Labonte: Volunteered Geographic Information: The Nature and Motivation of Produsers. In: International Journal of Spatial Data Infrastructures Research. 4, 2009, p. 334.
  36. ↑ Michael Goodchild: Commentary: whither VGI? In: GeoJournal. 72, No. 3–4, 2008, p. 240.
  37. ↑ David Coleman, Yola Georgiadou, Jeff Labonte: Volunteered Geographic Information: The Nature and Motivation of Produsers. In: International Journal of Spatial Data Infrastructures Research. 4, 2009, pp. 343/344.
  38. ↑ Andrew Flanagin, Miriam Metzger: The credibility of volunteered geographic information. In: GeoJournal. 72, No. 3–4, 2008, p. 142.
  39. ↑ Andrew Flanagin, Miriam Metzger: The credibility of volunteered geographic information. In: GeoJournal. 72 (3-4), 2008, pp. 139/140.
  40. ^ Sarah Elwood, Michael Goodchild, Daniel Sui: Researching Volunteered Geographic Information. Spatial Data, Geographic Research, and New Social Practice. In: Annals of the Association of American Geographers. 102, No. 3, 2012, p. 581.
  41. ↑ Andrew Flanagin, Miriam Metzger: The credibility of volunteered geographic information. In: GeoJournal. 72, No. 3–4, 2008, p. 143.
  42. ↑ Michael Goodchild, Linna Li: Assuring the quality of volunteered geographic information. In: Spatial Statistics. 1, 2012, p. 114.
  43. ↑ Data working group OpenStreetMap. Retrieved February 18, 2014.
  44. ↑ Michael Goodchild, Linna Li: Assuring the quality of volunteered geographic information. In: Spatial Statistics. 1, 2012, p. 115.
  45. ↑ Mordechai Hakley: Neogeography and the delusions of democratization. In: Environment and planning A. 45, No. 1, 2013, pp. 55/56.
  46. ↑ Michael Goodchild: Citizens as sensors: the world of volunteered geography. In: GeoJournal. 69, No. 4, 2007, p. 220.
  47. ↑ a b Mordechai Hakley: Neogeography and the delusions of demicratisation. In: Environment and planning A. 45, No. 1, 2013, p. 62.
  48. ↑ Christian Heipke: Crowdsourcing geospatial data. In: ISPRS Journal of Photogrammetry and Remote Sensing. 65, No. 6, 2010, p. 552.
  49. ↑ Muki Haklay: Citizen Science and volunteered geographic information: Overview and Typology of Participation. In: Daniel Sui, Sarah Elwood, Michael Goodchild, Michael (Eds.): Crowdsourcing Geographic Knowledge. Volunteered Geographic Information (VGI) in Theory and Practice. Springer Verlag, Dordrecht 2013, p. 113.
  50. ^ Sarah Elwood, Michael Goodchild, Daniel Sui: Researching Volunteered Geographic Information. Spatial Data, Geographic Research, and New Social Practice. In: Annals of the Association of American Geographers. 102, No. 3, 2012, p. 583.
  51. ↑ Christian Heipke: Crowdsourcing geospatial data. In: ISPRS Journal of Photogrammetry and Remote Sensing. 65, No. 6, 2010, p. 550.
  52. ↑ Christian Heipke: Crowdsourcing geospatial data. In: ISPRS Journal of Photogrammetry and Remote Sensing. 65, No. 6, 2010, p. 551.
  53. ^ Matthew Wilson, Mark Graham: Neogeography and volunteered geographic information: a conversation with Michael Goodchild and Andrew Turner. In: Environment and planning A. 45, 2013: 11.
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